Screw-threading tool.



No. 748,276. PATBNTBD 9120.29, 190s.f

o. E. GABRIEL. SCREW THRBADING TOOL.

APPLICATION FILED JULY 24, 1902.

NO MODEL.

' e fg s y mi mums Pzsns co.. PHA-nauwe., WASHINGTON n c UNITED L STATES Patented lecemloer 2 9, 1903. l

PATENT OFFICE. v

CHARLES R. GABRIEL, OF PROVIDENCE, RHODE ISLAND, AssIGNOR 'ro GORHAM MANUFACTURINGr COMPANY, oF PROVIDENCE, RHODE ISLAND SCREW-THREADING TOOL.

SPECIFICATION forming part of Letters Patent No. 748,276, dated December 29, 1903.

' Application filed July 24, 1902. Serial No. 116,784. (No model.)

To all whom it may concern:

Be it known that I, CHARLES R. GABRIEL, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented a new and useful Improvement in Screw-Threading Tools, of which the following is a specification.

This invention has reference to an improved tool adapted for use in a lathe for the threading ofthe ends of metal tubes; and it consists in the peculiar and novel construction illustrated in the drawings and more particularly described hereinafter.

Figure l is a side View of my improved tool. Fig. 2 is an end view of the same. Fig. 3 is a longitudinal sectional View of the tool, and

Fig. 4 is a transverse sectional view through the pinions connecting the two sleeves of the same.

In the drawings, A indicates the frame, of approximately U-shaped form. The arm ot forms the support of the stud B and the eccentric spindle C, while the arm a2 supports the end of the eccentric spindle. The stud B has the boss b at one end secured in the arm u and held against rotation by the pin b2, ex-

tending through the frame and the stud, as

is indicatedY in broken lines in Fig; 4. The projecting cylindrical portion b3 forms the journal-bearing for a sleeve having at one end the pinion b4 and on the other end the raised spirals b5. The washer h6 is secured to the end of the journal-bearing by the screw o7 and nut bs and holds the sleeve against longitudinal movement. The eccentric spindle has the cylindrical bearing c journaled in the arm a and the smaller cylindrical bearing journaled in the arm a2. The intermediate cylindrical portion c8 has its axis offset to one side of the axis of the journal-bearings The eccentric cylindrical portion c3 forms the support of a sleeve, on one end of which is the pinion c4. The other end of the sleeve has the raised spirals c5. Thepinions b4 and c4 engage with each other `and. cause the two sleeves to rotate in unison. The

raised spirals b5 and o5 are disposed so that the raised ribs of one spiral are between the raised ribs of the other spiral. The stud c6 projects from the cylindrical bearing c', and p to this stud the lever c7 is secured. The bracket cs projects from the lever and has the screw-post e9, by which the rotation of the eccentric spindle C is limited when the screwpost encounters the stop 01. The pin D projects from the frame A and has the recess d', into which the head d2 of the lever c7 enters to form a thrust-stop to prevent the longitudinal movement of the eccentric spindle C.

My improved screw-threading tool, which may be kept on hand, can be used on any lathe having a head-stock and an adjustable foot-stock. When required for use, the pin D is secured in the foot-stock, the tube E is secured in the chuck of the head-stock, and the foot-stock with the tool are moved toward the head-stock until the end of the tube E bears against the collar b9 on the screwthreaded sleeve. The eccentric spindle is now partially rotated by means of the lever c7 to bring the two screw-threaded sleeves with sufficient f'orce against the inner and outer surfaces of the shell of the tube and corrugate the same, as shown in Fig. 3 The rotation of the tube imparts rotary motion to the sleeves at the same time, they being connected by the pinions b4 and c4. A true screw-thread is thus formed on the endof the tube. When completed, the level` c7 is moved in the direction of the arrow'shown in Fig. 2; thereby partially turning the eccentric spindle C, raising the sleeve on the same off from the tube E, and bringing the pinion c4 against the friction-bar e, secured to the frame A, to arrest the rotation of the sleeves. The tube E, which is still rotating, unscrews from the sleeve on the cylindrical portion bs and acts to push the tool and the foot-stock backward ready to repeat the same operation on another tube.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. A portable screw-threading tool having an eccentric rotatable spindle and a xed cylindrical bearing provided with screw-threaded sleeves connected by gears, in combination with means for operatin g the same, as described.

2. In a portable screw-threading tool, the

combination with the frame and the cylindrical bearings supported in the frame, of a pair of sleeves rotatably mounted on the cylindrical bearings,raised screw-threads on the sleeves, pinion-gears on the sleeves, means for securing the tool to a sliding part of the lathe, and means for controlling the operation of the tool, as described. y

3. In a portable screw-threading tool, the combination with the frame A, the pin D on the frame, the stud B securedin the frame and the eccentric spindle C rotatably supported in the frame, of a sleeve rotatably supported on the stud B, the raised spirals b5 and thepinion b4 on the sleeve, a sleeve rotatably supported on the eccentric spindle C, the raised spirals c5 and the pinion c4 on the sleeve, and the lever c7 secured to the eccentric spindle, as described.

maar@ 4:. In a portable screw-threading tool, the combination with the frame A, the arm ct and the arm a2 on the frame, the stud B secured in the frame and the eccentric spindle C rotatably supported in the frame, of a sleeve supported on the eccentric spindle, the raised spirals@5 and the pinion c4 en the sleeve, the friction-bar e on the frame, a sleeve on the cylindrical portion b3 of the stud B, the raised spirals b5, the collar b9, and the pinion b4 on the sleeve, the pin D projecting from the frame, and the lever c7 secured to the eccentric spindle C, as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

CHARLES R. GABRIEL.

Witnesses:

JOSEPH A. MILLER, BELLE SIMMs WEBSTER. 

